A great screentime tracker. Simple, minimalist interface, customizable settings, data visualization. Free, open source.
The best tool I have used for turning your phone into a mouse and keyboard for your pc. Free, open source. Can also be used to send files between your phone and pc, use pc keyboard for input on your phone, etc. Has other features too.
Fully open-source, end-to-end encrypted notes with device-based security, secure sync, offline access, powerful editor, vault, backups, and exports.
JustNotes is simple android app for taking notes, like there have been tens of thousands before. App uses Room database.
NeeView is a Free and Open Source, modern and powerful image viewer and a manga/comic reader that has high quality scaling options and many different customization options.
A free and open source podcastmanager for Android, allowing you to subscribe to podcasts (via iTunes database & OPML), automatically download episodes using powerful mechanisms and listen to them the way you like (speed, balance adjustments, etc).
Tsacdop is a podcast player developed with Flutter, a clean, simply beautiful and friendly app, which is also free and open source.
A full-featured, lightweight video & audio player. Highly customizable. Has all the features that I could ever need for a video player.
A simple, straightforward tool for video coding. I use it to compress videos and burn subtitles into videos. Free, zero ads, no internet required.
An open-source multithreaded video transcoder, HandBrake compresses and converts digital media, supporting MP4, MKV formats, and offers hardware-accelerated conversion.
Command line program that's a 
youtube-dl fork that downloads videos from YouTube and over 1000 sites. The main focus of this project is adding new features and patches while also keeping up to date with the original project.
The qBittorrent project aims to provide an open-source software alternative to µTorrent. Additionally, qBittorrent runs and provides the same features on all major platforms (FreeBSD, Linux, macOS, OS/2, Windows). qBittorrent is based on the Qt toolkit and libtorrent-rasterbar library.
Highly customizable, supports user-made dictionaries. Translation, notebooks for saved words, a floating icon feature that can be used to search words quickly while in other apps, vocab building feature (a wide variety of premade and custom word-lists). The free version on android has all the features I need. The pc version has more restrictions for free users.
